#include<iostream>
#include<vector>
#include<algorithm>

using namespace std;

int maxProfit(vector<int>& prices)
{
    int n = prices.size();
    vector<vector<int>> dp(n, vector<int>(3));
    dp[0][0] = -prices[0];

    for (int i = 1; i < n; i++)
    {
        dp[i][0] = max(dp[i - 1][0], dp[i - 1][1] - prices[i]);
        dp[i][1] = max(dp[i - 1][1], dp[i - 1][2]);
        dp[i][2] = dp[i - 1][0] + prices[i];
    }

    return max(dp[n - 1][1], dp[n - 1][2]);
}

int main()
{
    vector<int> v = { 1,2,3,0,2 };

    cout << maxProfit(v) << endl;

	return 0;
}